The invention relates to a measuring apparatus for measuring forces which occur when clamping a rotary body on to a drive shaft of a testing machine, for example a balancing machine.
In this specification the term rotary body is used to denote a rotary member such as a wheel which may be in need of balancing, and a rotary member substitute body which is adapted for example to simulate a characteristic of a rotary member, such as for example its rigidity or strength as in a radial direction.
The purpose of conventional clamping arrangements as are used for example as an ancillary device on a wheel balancing machine for holding a wheel to be balanced in position for the balancing operation is to provide for radial centering of the workpiece or rotary member to be balanced, and to provide for reliable transmission of the drive moment from the drive shaft to the workpiece or rotary member which is carried on the drive shaft itself, without slippage of the rotary member. In that situation however the workpiece or rotary member is to be clamped in position in such a way that no surface pressure phenomena or markings or the like remain on the member.